The invention relates to a method of determining the standard color data of colors represented on a color monitor. Within a color represented on the color monitor there is fixed a measurement area in which the color measurement data are determined. From the color measurement data there are calculated the corresponding standard color data of the color selected by the measurement area, taking into account the tube characteristics and the standard color data of the individual phosphors of the color monitor.The accuracy of the determination of standard color data can be increased by multiple measurement within the measurement area.The calculated standard color data are, for example, the starting quantities for a color mixture calculation by means of a color formula computer.